Abstract: A timing system for a three dimensional vibrating mirror display which controls the display of information throughout the varying rate of sweep through the display volume characteristic of such systems and assures proper interlacing of the forestroke and backstroke images in a simple efficient manner is disclosed. The system includes an anisochronous clock which varies its clocking rate in proportion to the momentary velocity of movement through the display volume so that the displayed image planes are equally spaced throughout the depth of the display volume. The anisochronous clock of the invention utilizes a relatively simple circuit to sequentially address a read-only memory in effect containing predetermined information regarding the velocity of sweep through the display volume for each position of the vibrating mirror, which information is used to generate a clock signal for controlling the display.